Laserfiche WebLink
California 'egional Water Quality Coi of Board /- <br /> i1l�w; Central Valley Region 'z f <br /> Karl E. Longley,ScD P.E. Chair <br /> g y, , <br /> Linda S.Adams Main Sacramento ain Office <br /> Secretary for Schwarzenegger <br /> Enruonmenta/ 11020 Sim Center Drive 4200,Rancho Cordova,California 956706114 Gorernor <br /> Protection Phone(916)464-3291 •FAX(916)464-4645 <br /> http://www.�aaterboards.ca.gov/centralval]eN <br /> MD <br /> 28 May 2008 <br /> Cr <br /> Ms. Stephanie Furgal MAY 3 0 2008 Mr. Phil Johnson <br /> Chevron Environmental Management Company ENVIRONMENT HEAL Aims-Group Management <br /> P.O. Box 6004 PERnfIT;SERVICES 4 Lincoln Center <br /> San Ramon, CA 94583 Stockton, CA 95207 <br /> REVIEW, CHEVRON #9-6171, 6633 PACIFIC AVENUE, STOCKTON, SAN JOAQUIN <br /> COUNTY <br /> I reviewed the Work Plan For Additional Soil Assessment (Workplan), submitted on behalf of <br /> Chevron Environmental Management Company (Chevron) by Arcadis. The Workplan <br /> proposes one Cone Penetrometer Testing (CPT) boring to investigate the vertical extent of soil <br /> contamination previously found in December 1997 beneath former Waste Oil Tank 1 (WOT-1). <br /> Maximum soil contamination concentrations from WOT-1 were total petroleum hydrocarbons <br /> as gasoline (TPHg), 110 milligrams per kilogram (mg/kg); TPH as diesel (TPHd), 4,900 mg/kg; <br /> TPH as motor oil (TPHmo), 7,400 mg/kg; a combined analysis (total) for benzene, toluene, <br /> ethylbenzene, and xylenes, 8.4 mg/kg; and chlorinated solvents cis-1,2-dichloroethene <br /> (cis-1,2-DCE), 2.2 mg/kg and tetrachloroethene (PCE), 1.5 mg/kg. The Workplan states the <br /> Cam 5 metals and polychlorinated byphenols (PCBs) were not detected in soil in <br /> December 1997 at WOT-1. Soil samples will be collected from 10 feet bgs to the anticipated <br /> groundwater table at 37 feet bgs, and approximately 6 samples (from 5-foot intervals) will be <br /> analyzed for cis-1,2-DCE and PCE by USEPA Method 8U60B. <br /> Comments: The Workplan is approved with the following changes: <br /> 1 . Include the recommended analyses for investigation of waste oil tanks from Table 2 <br /> (Enclosed) of Appendix A — Reports, Tri - Regional Board Staff Recommendations For <br /> Preliminary Investigation And Evaluation Of Underground Tank Sites, dated 16 April <br /> 2004. Table 2 recommends TPHg by USEPA Method 8015M or 8260B, TPHd by <br /> USEPA Method 8015M, Volatile Organic Compounds (VOCs include cis-12,-DCE and <br /> PCE) by USEPA Method 8260B, Semi-volatile Organic Compounds (Semi-VOCs) by <br /> USEPA Method 8270C, Oil and Grease by USEPA Method 1664A, and Title 22 Metals <br /> by USEPA Method Series 6000/7000. <br /> 2. Also include BTEX by 8021 B or 8260B (8021 B requires one duplicate sample also be <br /> run by 8260B for verification) and TPHmo by 8015M, since total BTEX and TPHmo <br /> were detected in December 1997. <br /> 3. Since PCBs were not detected in December 1997, you may skip the PCBs analysis. <br /> 4. All soil data results shall be comparable to San Francisco Bay Regional Board <br /> California Environmental Protection Agency <br /> cla RecYcled Paper <br />